Radiotherapy uses carefully measured doses of radiation to treat cancer. The most common type of radiotherapy uses beams of high-energy rays, usually x-rays. The radiotherapy machine aims specific amounts of the radiation only to the area of the body that it is pointed at and nowhere else.
Radiotherapy works because the high dose of radiation damages cells and stops them from growing and dividing. Normal cells that are affected usually recover or repair themselves quite quickly. Cancer cells, which are abnormal cells, do not recover. Any side effects, which occur during treatment, are usually temporary.
Benefits of radiotherapy
The purpose of radiotherapy is to destroy the cancer cells while causing as little damage as possible to normal cells. It can be used to treat many kinds of cancer in almost any part of the body. Curative treatment, which is sometimes called radical treatment, aims to give long-term benefits to people. Sometimes radiotherapy is given on its own or it may be given alongside other treatment.
Radiotherapy may be given before surgery to shrink a tumour or after surgery to stop the growth of cancer cells that may remain. It can also be given before, during, or after chemotherapy (anti-cancer drugs) to improve treatment results.
Palliative treatment aims to shrink tumours and reduce pain or relieve other cancer symptoms. While a cure is not likely, palliative radiotherapy may also prolong life.
Risks of radiotherapy
Radiotherapy can damage or destroy normal cells as well as destroying cancer cells and cause treatment side effects. Most side effects are temporary and your doctor will not advise you to have any treatment unless the benefits – control of disease and relief from symptoms – are greater than the known risks.
You should not become pregnant before or during radiotherapy because radiotherapy may injure the foetus, especially in the first three months of a pregnancy. Please discuss with your doctor if you think you may be pregnant. Your doctor will also be able to advise you on how long you should wait before becoming pregnant.
Some doctors advise men against fathering a child during radiotherapy and for a few months afterwards. Again, your doctor will be able to discuss this with you.